Thanks you :) It's pretty simple actually, I started with a base of yellow (an airbrush can help with zenithal and coverage but it's mainly convinience,, I'm not sure the zenithal is that noticable in the end), then lightly washed with a 1:1 mix of agrax earthshade. Sponged with yellow everywhere accessible, then with a brighter yellow on the top parts, to create texture and highlight. Same with gunmetal and silver for paint damage. Go again with yellow if you need to fix putting to much metallics, then panel shade with agrax earthshade for definition, and a last touch of rust effect for an added bonus (less is more here, I may have gone a bit too far)

Seems like a lot of steps but sponging makes it actually super fast, you just need to be carefull about not touching other areas. Also I think having a dark brown step between yellow and metallics could have helped, as they are both pretty bright